Improvement in the manufacture of india-rubber rolls



W. C A B L E.

improvement in the Manufacture of India-Rubber Rolls.

N0. 125,787, Patented April16,1872.

Invenl-ar v W KW Ma,

7 Jun. ma /1M. ogawmm V I WHEELER CABLE, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN THE MANUFACTURE OF INDIA-RUBBER ROLLS.

.Specification'forming part of Letters Patent No. 125,787, dated April 16, 1872.

To all whom it may concern:

Be it known that I, W EELER CABLE, of Boston, in the county of Sulfolk and State of Massachusetts,haveinvented an Improvement in the Manufacture of Elastic Rolls 5 and I do hereby declare that the following, taken in connection with the drawing which accompanies and forms part of this specification, is a description of my invention sufficient to enable those skilled in the art to practice it.

My invention relates to the manufacture of that class of elastic rollers, in the con struction of which, the core or interior portion of the elastic body is first formed, and the exterior portion thereof, or envelope, is then applied to the core and united with it the invention more especially appertaining to the mode of construction of those of such elastic rollers in which the core is formed of contiguous layers or strips of vulcanizable India-rubber compound, so arranged in relation to each other as to present their edges at the periphery of the core. This will be readily understood by reference to a certain well-known manufacture of elastic rollers to which my im provementis particularly applicable, and of which the following is a brief description In the manufacture of a wellknown elastic roller of this kind, a series of parallel yarns or threads (arranged like warpyarns) is laid between two sheets of vulcanizable India-rubber compound, which sheets, with the inclosed yarns or threads, are run between calendar-rollers, thereby making a single composite sheet from which narrow strips are out directly across the strings or threads, these strips being joined end to end to form a single continuous strip of any desired length, which is folded at its center upon a wire, so as to bring its opposite edges side by side with the wire in the bottom of the fold. The core of the elastic roller is then made by winding the wire and its enveloping strip spirally around the roller-shaft, in such manner as to bind the center of the fold upon the shaft to pack the sides of the folded strip, and of the consecutive coils closely together, and to present the edges of the strip side by side, and peripherally outward. Theoperations of folding the strip, laying the wire within it, and winding them together upon the shaft, as described, are usually performed by the aid of suitable machinery organized for that purpose, it being requisite that the wire should be fastened to the shaft and wound upon it under considerable tension, in order to securely attach the core, and that the spirally-wound layers should be packed tightly togetherin the act of winding the strip, in order to give the proper coherence and firmness to the core. To complete the construction of an elastic roller having substantiall y such a core as I have described, it has been the practice sometimes to smear the periphery of the core with an India-rubber cement, so as to promote more intimate union between the core and its envelope, and then to wrap about it a sheet of vulcanizable Indiarubber compound, until the required enveloping thickness was obtained, and afterward to inclose the whole within a suitable cylindrical mold and sometimes to prepare the envelope or sleeve in the shape of a tube of proper thickness, and after inserting it within the mold, to force the core into it, the bore of the tube as well as the periphery of the core being previously smeared with the Indiarubber cement; the mold and its contents being then placed in the vulcanizing-chamber in which the elastic roller is properly cured. This latter mode of covering elastic rollers, although a very useful one, and an improvement upon the first-named method, has yet been attended with certaindefects and difficulties which it is the merit of my invention to have obviated. In the process of vulcanizing, the elastic envelope or sleeve contracts upon the core in such manner, that the irregularities of the periphery of the core cause corresponding irregularities upon the periphery of the vulcanized roller, which irregularitieshave to be removed by abrasion in order to finish the roller for the market. This is usually accomplished by rotating the roller in alathe, and applying sand-paper to its surface until it assumes a more perfect cylindrical shape, requiring the expenditure of a great amount of time and labor, and involving serious disadvantages, which arise from the peculiar preparation which has to be made in the outer coating of the elastic envelope of the roller in order to fit it to be abraded, the softer India-rubber compound, of which it is desirable that the elastic body of the roller should be made, not being readily ground away, nor reducedto a sm oothly finished surface under the action of the sand 2 raeyev paper; for which reason it becomes necessary to make the outer portion of the elastic envelope of a harder and more readily-abraded India-rubber compound than that of which its interior portions are composed. Such a construction impairs the value of the elastic roller, especially for use in clothes-wringin g machines, since it is not practicable in the process of finishing to remove all of this harder outer coating, and therefore the elasticity of the roller is diminished at the very places where it is important to preserve at least as much elasticity as exists elsewhere within its body.

My invention consists in so preparing the core of an elastic roller, that it will present a substantially regular cylindrical surface to the elasticenvelope or encompassing sleeve with which it is to be surrounded, and at the same time will retain its capability of thorough union with that envelope during the process of vulcanization. By this means the irregular contraction of the elastic envelope is prevented, and the vulcanized roller comes from the mold with a smooth cylindrical surface, having a finish much superior to that which can be given by grinding or abrasion. The mode in which I find it convenient to carry out my invention, is as follows, namely: After the core of the elastic roller has been constructed as I have hereinbefore indicated or described, it is placed under pressure within a cylindrical mold of a size somewhat smaller than itself, andis there subjected for a short time to heat sufficient to render plastic the vulcanizable India-rubber compound of which it is composed, and to give it a permanent cylindrical contour, at the same time making it firmer and more coherent without vulcanizing it to such a degree as to materially affect its subsequent intimate union with the elastic envelope. The cylindrical core the shaft as it appears after the core, prepared as described, has been subjected to heat and pressure in a cylindrical mold to first render the wound compound plastic, and then impart its permanent cylindrical form. E and F show similar views of one end of the finished roll, or the roll shown at O and D covered by the adhering vulcanizable envelope.

(t denotes the shaft or mandrel; b, the strip folded and spirally wound upon the shaft; 0,

the wire at the bottom of the fold; d, the cyl-' indrieal surface to which the irregular edges of the strip are brought by molding and vulcanizing under pressure; 0, the envelope or jacket with which the surface (1 is covered to form the finished roll.

I claim 1. The mode of preparing the core for the reception of the encompassing sleeve or envelope, substantially as described.

2. The core of vulcanizable India-rubber compound formed and made cylindrical, substantially as described.

3. The elastic roll, havinga core and a core enveloping or encompassing sleeve, the core being formed and made cylindrical and then covered, all substantially as described.

IVHEELER CABLE. Witnesses:

FRANcrs GOULD, M. W. FROTI-IINGHAM. 

